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    <title>Document</title>
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<body>
    <style>
        .div p{
            color: red;
        }
        .div>p{
            color: green;
        }
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    <div class="div">
        <p>啪啪啪啪啪</p>
    </div>

    <div class="div">
        <div>
            <p>啪啪啪啪啪</p>
        </div>
    </div>

</body>
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